I've never asked your question but as far as I know, there are no "Ribbon Police" after you have successfully completed a campaign. If you cannot improve a finished model on your own without losing a ribbon then I'd have to give half of mine back.
I often use my Campaign models to enter into our club contests and sometimes I have to do a little more work before I'm satisfied.
Maybe others have different views or opinions?
Many thanks for your kind reply mate Don Yeah, just a little worry about that.. I just don't want to let anyone down if such term maybe applied without I know before If so, I will perform my best effort on the re-improvement work in the next couple days and I will share the job, many thanks again mate Don!
Warm regards from Indonesia,